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排序方式: 共有10000条查询结果,搜索用时 154 毫秒
41.
Vidal-Sanz M Lafuente M Sobrado-Calvo P Selles-Navarro I Rodriguez E Mayor-Torroglosa S Villegas-Perez MP 《Neurotoxicity research》2000,2(2-3):215-227
In adult Sprague-Dawley rats, retinal ganglion cell survival was investigated after intraorbital optic nerve section and after transient ischemia of the retina induced by elevation of the intraocular pressure or by selective ligature of the ophthalmic vessels. The thickness of the inner nuclear and inner plexiform layers was also assessed after transient periods (120 min) of retinal ischemia induced by selective ligature of the ophthalmic vessels. In addition, we have also investigated the neuroprotective effects of different substances in these paradigms. The intraocular injection of brain-derived neurotrophic factor increased RGC survival after retinal ischemia induced by elevation of the intraocular pressure or by selective ligature of the ophthalmic vessels. The caspase-inhibitor Z-DEVD increased retinal ganglion cell survival after optic nerve section and also after 90 min of retinal ischemia induced by selective ligature of the ophthalmic vessels. The peptide Bcl-2 did not increase retinal ganglion cell survival after optic nerve section but increased retinal ganglion cell survival after 60 or 90 min of retinal ischemia induced by selective ligature of the ophthalmic vessels. Finally, BDNF, nifedipine, naloxone and bcl-2 prevented in part the decrease in thickness of the inner nuclear layer and inner plexiform layer induced by selective ligature of the ophthalmic vessels. Our results suggest that retinal ganglion cell loss induced by different types of injury, may be prevented by substances with neuroprotective effects, by altering steps of the cascade of events leading to cell death. 相似文献
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43.
Oehninger S 《Fertility and sterility》2008,89(1):27-30
It is agreed that ovarian stimulation results in histopathologic changes and variations in gene expression when compared to natural cycles. However, the enigma is still present: What is the true impact of variable degrees of embryo-endometrium developmental asynchrony in the presence of high clinical embryo implantation rates in IVF? It is postulated that the temporal characterization of gene expression and protein profiles of isolated endometrial compartments might unveil patterns that are critical for the establishment of the window of implantation. 相似文献
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Arslan M Bocca S Arslan EO Duran HE Stadtmauer L Oehninger S 《Journal of assisted reproduction and genetics》2007,24(4):111-117
Purpose: To investigate the effect of the cumulative exposure to estradiol (E2) during the follicular phase on IVF outcome.
Methods: Patients were stimulated with recombinant FSH after GnRH agonist suppression and had a day 3-embryo transfer. Estrogen exposure
was determined as the area under the curve (AUC) for serum E2 levels measured from the first day of stimulation through the day after hCG administration.
Results: E2 AUC thresholds for 10th and 90th percentiles were 4704 pg/ml and 16338 pg/ml, respectively. The pregnancy and implantation
rates were highest in the 10th–90th percentile group, and were statistically higher in this group than in the >90th percentile
group (54.6% vs. 33.3% and 24.8% and 12.9%, respectively, for pregnancy and implantation rates, P < 0.05). Recovered mature oocytes, fertilization, and number and mean score of transferred embryos were similar.
Conclusions: High cumulative E2 exposure during the follicular phase of IVF cycles has detrimental effects on implantation. 相似文献
46.
Current status of robotically assisted laparoscopic surgery in reproductive medicine and gynaecology
Laparoscopic techniques have revolutionized the concept of minimally invasive surgery. Robotically assisted surgery is one of the latest innovations in this field and many operative laparoscopic procedures have been performed in urology, cardiac and general surgery. More recently, the use of robotically assisted techniques have been introduced in gynaecology, and most available studies have shown it to be a safe and effective alternative to conventional laparoscopic surgery. However, whether or not to approach the management of certain gynaecological pathologies with a laparotomy or laparoscopy (conventional or with robotic aid) continues to be a point of debate. This article reviews recent developments in the endoscopic management of reproductive (tubal reanastomosis and myomectomies) and other gynaecological surgical conditions (hysterectomies, pelvic organ prolapse, repair of vesicovaginal fistulas and staging for gynaecological malignancies). Ongoing controversies associated with this technology, such as cost, learning curve, conversion rate to laparotomy, post-surgical fertility and complications, are briefly addressed. Long-term analysis of outcomes is ongoing. 相似文献
47.
Eleonora Loi Cesare Zavattari Alessandro Tommasi Loredana Moi Matteo Canale Agnese Po Claudia Sabato Ana Florencia Vega-Benedetti Pina Ziranu Marco Puzzoni Eleonora Lai Luca Faloppi María Rulln Juan Carrascosa Irene Amat Jesús M. Urman Maria Arechederra Carmen Berasain Elisabetta Ferretti Andrea Casadei-Gardini Matías A. Avila Sergio Alonso Mario Scartozzi Patrizia Zavattari 《British journal of cancer》2022,126(12):1783
Background Biliary tract cancers (BTC) are rare but highly aggressive tumours with poor prognosis, usually detected at advanced stages. Herein, we aimed at identifying BTC-specific DNA methylation alterations.Methods Study design included statistical power and sample size estimation. A genome-wide methylation study of an explorative cohort (50 BTC and ten matched non-tumoral tissue samples) has been performed. BTC-specific altered CpG islands were validated in over 180 samples (174 BTCs and 13 non-tumoral controls). The final biomarkers, selected by a machine-learning approach, were validated in independent tissue (18 BTCs, 14 matched non-tumoral samples) and bile (24 BTCs, five non-tumoral samples) replication series, using droplet digital PCR.Results We identified and successfully validated BTC-specific DNA methylation alterations in over 200 BTC samples. The two-biomarker panel, selected by an in-house algorithm, showed an AUC > 0.97. The best-performing biomarker (chr2:176993479-176995557), associated with HOXD8, a pivotal gene in cancer-related pathways, achieved 100% sensitivity and specificity in a new series of tissue and bile samples.Conclusions We identified a novel fully efficient BTC biomarker, associated with HOXD8 gene, detectable both in tissue and bile by a standardised assay ready-to-use in clinical trials also including samples from non-invasive matrices.Subject terms: Diagnostic markers, Biliary tract cancer 相似文献
48.
Shaji Kumar Lawrence Baizer Natalie S. Callander Sergio A. Giralt Jens Hillengass Boris Freidlin Antje Hoering Paul G. Richardson Elena I. Schwartz Anthony Reiman Suzanne Lentzsch Philip L. McCarthy Sundar Jagannath Andrew J. Yee Richard F. Little Noopur S. Raje 《Blood cancer journal》2022,12(6)
A wide variety of new therapeutic options for Multiple Myeloma (MM) have recently become available, extending progression-free and overall survival for patients in meaningful ways. However, these treatments are not curative, and patients eventually relapse, necessitating decisions on the appropriate choice of treatment(s) for the next phase of the disease. Additionally, an important subset of MM patients will prove to be refractory to the majority of the available treatments, requiring selection of effective therapies from the remaining options. Immunomodulatory agents (IMiDs), proteasome inhibitors, monoclonal antibodies, and alkylating agents are the major classes of MM therapies, with several options in each class. Patients who are refractory to one agent in a class may be responsive to a related compound or to a drug from a different class. However, rules for selection of alternative treatments in these situations are somewhat empirical and later phase clinical trials to inform those choices are ongoing. To address these issues the NCI Multiple Myeloma Steering Committee formed a relapsed/refractory working group to review optimal treatment choices, timing, and sequencing and provide recommendations. Additional issues considered include the role of salvage autologous stem cell transplantation, risk stratification, targeted approaches for genetic subsets of MM, appropriate clinical trial endpoints, and promising investigational agents. This report summarizes the deliberations of the working group and suggests potential avenues of research to improve the precision, timing, and durability of treatments for Myeloma.Subject terms: Combination drug therapy, Cancer therapeutic resistance, Targeted therapies 相似文献
49.
50.
Bruno Guedes Baldi Alexandre Todorovic Fabro Andreia Craveiro Franco Marília Helena C Machado Robson Aparecido Prudente Estefnia Thom Franco Sergio Ribeiro Marrone Simone Alves do Vale Talita Jacon Cezare Marcelo Padovani de Toledo Moraes Eloara Vieira Machado Ferreira Andr Luis Pereira Albuquerque Marcio Valente Yamada Sawamura Suzana Erico Tanni 《Jornal brasileiro de pneumologia》2022,48(3)